This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AM3894: Recovery from HOSTPEND error condition in EMAC

Part Number: AM3894

The TRM for AM389x (SPRUGX7C) states the following about recovering from a HOSTPEND error condition:

  • A hardware reset is the only means of recovering from the error interrupts (HOSTPEND), which are triggered by errors in packet buffer descriptors. Before doing a hardware reset, you should inspect the error codes in the MAC status register (MACSTATUS) that gives information about the type of software error that needs to be corrected.

However, the means of initiating a hardware reset on the EMAC module isn't stated in any obvious way in the TRM (at least that I can find).  Does anyone know how to initiate a hardware reset of the EMAC module? 


Thanks!

  • Shane,

    Per mine understanding, you should initiate hardware reset of the AM389x device, not to EMAC only. You should initiate Power On Reset (PORn pin) or External Warm Reset (RESETn pin).

    There are also local resets in AM389x device PRCM - The local reset for various modules within the device is controlled by programming the PRCM and the module's internal registers. Only the associated module is reset when a local reset is asserted, leaving the rest of the device unaffected. But EMAC belongs to Always on power domain, which can not be reset locally, thus full device reset is needed.

    Regards,
    Pavel
  • Pavel,

    That makes sense. My first instinct was to look for an EMAC local reset in the PRCM module, but I didn't find anything. I didn't realize that the EMAC belonged to an "Always On" power domain and couldn't be reset locally, and that a full device reset was required to clear a HOSTPEND error condition. I really appreciate your response!

    Regards,
    Shane